Vicinity of Mason Creek, Illinois. 



367 



Handlirsch (Fossil Insects, 1. 15, f. 15), has a very singular organ 

 at the apex of the abdomen (see fig. 48). A careful examina- 

 tion shows that it reaches as far as the eighth segment and 

 bears a longitudinal suture. There can be scarcely any doubt 

 that it is a larval ovipositor. On one side of this organ a 

 distinct cercus is preserved. The sides of the segments are 

 lobate, the wing cases somewhat spread outward and backward. 

 The comparatively short and stout legs are inserted very near 

 the middle line. The head with its large eyes lies free in 

 front of the pronotum. Head, body and ovipositor together 

 have a length of 22 mm . 



It is very possible that this larva is of JEucoenus or a 

 related form. 



Another larva, contained in my work under the name (Pro- 

 toblattoidea) sellardsi Handlirsch (p. 152, t. 15, f. 14), seems to 

 be closely related to the above mentioned species, the stout 



Fig. 50. 



Fig. 50. Adeloblatta sellardsi. x 2-3. 



and short legs being very similar to Puccenus. This fossil 

 (see fig. 49), with comparatively shorter wing cases than (P.) 

 minor, is probably in a more juvenile stage but nevertheless 

 much larger (somewhat more than 30 mm ), so that it must be 

 considered as a distinct species. 



Holotypes in Peabody Museum, Yale University, Cat. Nos. 

 57, 58. 



Order BLATTOIDEA Handlirsch. 



Family ARCHIMYLACKID^E Handlirscli. 



Adeloblatta sellabdsi (Handlirsch). Fig. 50. 



Etoblattina liillianaf Sellards, Aruer. Jour. Sci. (4), xviii, 



1904, p. 213, pi. 1, fig. 4. 

 Phyloblatta sellardsi Handlirsch, Foss. Insects, 1906, p. 205, t. 21, 



f. 15. 



Sellards ' first figure did not show clearly enough the rami- 

 fication of the media and so I was misled into placing the 



